Linking the Mardi Gras capital of New Orleans in Louisiana and the waterfront city of Mobile in Alabama, Amtrak’s Gulf Coast train is set to become one of the USA’s great rail routes once more when it relaunches in spring 2025. Following the southern US shoreline for most of its three-hour journey, it passes through Louisiana’s Cajun country — known for its miles of bayous, traditional festivals and hearty gumbos (spicy Cajun chicken soup) — and coastal Mississippi.